Medical device visualization system

ABSTRACT

Embodiments of the disclosure may include a medical device comprising an elongate member including a proximal region and a distal region. The elongate member can further include a handle at the proximal region and a tip at the distal region. The tip can include one or more openings, wherein one of the one or more openings at least partially houses an illumination unit. The illumination unit may further comprise a light source, a near-field diffuser proximate to the light source, and a far-field aperture proximate to the light source.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority from U.S. ProvisionalApplication No. 61/659,258, filed on Jun. 13, 2012, the entirety ofwhich is incorporated by reference herein.

FIELD OF THE DISCLOSURE

Embodiments of the present disclosure include medical devices, and moreparticularly, medical devices including enhanced visualization andmethods of use.

BACKGROUND OF THE DISCLOSURE

Adequate visualization has posed a challenge in the exploration andtreatment of internal areas of the human body. Visualization may beespecially troublesome in minimally invasive procedures in which smalldiameter, elongate instruments, such as catheters or endoscopes, may benavigated through natural passageways and cavities of a patient to aregion of interest (work site).

In conventional minimally invasive procedures, an endoscope or cathetermay be inserted into the body for diagnostic or therapeutic purposes. Adistal end of an endoscope may be inserted into the body through anopening in the body. This opening may be a natural anatomic opening,such as, for example, the mouth, rectum, vagina, etc., or an incisionmade on the body. The endoscope may be pushed into the body such thatthe distal end of the endoscope proceeds from the point of insertion toa work site within the body by traversing a body lumen, for example, thegastric, pulmonary, esophageal, or urological tracts.

Once inside the body, performing diagnostic and treatment proceduresrequires sufficiently clear visualization. Navigating and identifyingregions of interest may require down-lumen visualization. For down-lumenvisualization, high-intensity light with a small spot size may bedirected towards the center of a body lumen. When directed towardsnear-field objects, however, this light may become saturating and imagedetails may be lost. By contrast, visualizing the near-field lumenperiphery may require wide-angle, low-intensity light. While suchlow-intensity light avoids saturation of near-field objects, it may notprovide enough illumination to visualize down lumen. These variations inillumination requirements may make navigation and visualization of thework site difficult, potentially increasing procedure time anddecreasing accuracy, and thus increasing the possibility ofcomplications for the patient.

Conventional endoscopes may utilize complex and/or expensive systems,such as arrays of optical fibers or light-emitting diodes (“LEDs”) at adistal region of an endoscope in order to provide uniform illuminationin both the near and far fields. But such devices may increase the sizeof endoscopes, making them cumbersome to maneuver and restricting thecavities through which they may pass. Additionally, they may increasethe cost of manufacturing and maintaining these instruments.

Accordingly, a need exists for a compact, cost-effective visualizationunit capable of achieving adequate uniform far-field and near-fieldillumination. The medical devices and related methods of the presentdisclosure are directed to improvements in the existing technology andovercome at least some of the deficiencies in the prior art.

SUMMARY OF THE DISCLOSURE

Various embodiments of the disclosure may include one or more of thefollowing aspects.

In accordance with one embodiment, a medical device may comprise anelongate member including a proximal region and a distal region. Theelongate member can further include a handle at the proximal region anda tip at the distal region. The tip can include one or more openings,wherein one of the one or more openings at least partially houses anillumination unit. The illumination unit may further comprise a lightsource, a near-field diffuser proximate to the light source, and afar-field aperture proximate to the light source.

In accordance with another embodiment, a medical device may comprise anelongate member including a proximal region and a distal region and oneor more channels extending from the proximal region to the distalregion. A channel of the one or more channels may be configured to carrylight or a light signal to a distal region of the elongate member. Thelight or light signal may be from only one optical fiber or only onelight emitting diode. Additionally, the medical device can include anear-field diffuser at the distal region of the elongate memberconfigured to provide near-field illumination. The medical device canalso include a far-field aperture at the distal region of the elongatemember configured to provide far-field illumination. The medical devicemay also include an imaging unit.

In this respect, before explaining multiple embodiments of the presentdisclosure in detail, it is to be understood that the present disclosureis not limited in its application to the details of construction and tothe arrangements of the components set forth in the followingdescription or illustrated in the drawings. The present disclosure iscapable of embodiments in addition to those described and of beingpracticed and carried out in various ways. Also, it is to be understoodthat the phraseology and terminology employed herein, as well as in theabstract, are for the purpose of description and should not be regardedas limiting.

The accompanying drawings illustrate certain exemplary embodiments ofthe present disclosure and, together with the description, serve toexplain the principles of the present disclosure. As such, those skilledin the art will appreciate that the conception upon which thisdisclosure is based may readily be used as a basis for designing otherstructures, methods, and systems for carrying out the several purposesof the present disclosure. It is important, therefore, to recognize thatthe claims should be regarded as including such equivalent constructionsinsofar as they do not depart from the spirit and scope of the presentdisclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a medical device, according to an exemplary disclosedembodiment;

FIG. 2A illustrates a perspective view of a distal region of a medicaldevice, according to an exemplary disclosed embodiment;

FIG. 2B illustrates a cross-sectional view of a distal region of amedical device, according to an exemplary disclosed embodiment;

FIGS. 3A-3B illustrate end views of exemplary distal ends of a medicaldevice, according to exemplary disclosed embodiments; and

FIG. 4 illustrates a cross-sectional view of a distal region of amedical device, according to an exemplary disclosed embodiment.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary embodiments of theinvention, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts. Also, anyaspect set forth in any embodiment may be used with any other embodimentset forth herein.

The terms “proximal” and “distal” are used herein to refer to therelative positions of the components of an exemplary medical device.When used herein, “proximal” refers to a position relatively closer tothe exterior of the body or closer to the physician, or other user,using the medical device. In contrast, “distal” refers to a positionrelatively further away from the user using the medical device or closerto the interior of the body.

While the described systems and methods may generally refer to medicaldevices and procedures, the described systems and their methods of useare not limited to any particular medical diagnostic or treatmentprocedure. Moreover, the systems and devices described herein canperform nonmedical applications, such as the inspection or repair ofmachinery.

FIG. 1 illustrates a medical device 1 according to an exemplaryembodiment. Medical device 1 may include any device configured to allowan operator to access and view internal body anatomies of a patient.Such devices include, for instance, an endoscope, a catheter, a guidetube, or the like. Medical device 1 may be configured for insertion intoa variety of body lumens and/or cavities, such as, for example, anyportion of a urinary tract including a ureter, a gastrointestinal lumenincluding an esophagus, a biliary duct, pancreatic duct, a vascularlumen, an airway, and the like. Medical device 1 also may be used, forexample, in natural orifice transluminal endoscopic surgery (NOTES)procedures or single incision laparoscopic surgical (SILS) procedures.Accordingly, medical device 1 can be shaped and sized for placement intoa patient via a body cavity or an incision. For purposes of the presentdisclosure, medical device 1 may include a single-use, disposableendoscope, or medical device 1 may include a reusable endoscope.

Medical device 1 may include an elongate member 3 having a proximal endand a distal end. A handle assembly 2 may be operably connected to aproximal region of elongate member 3 and configured for steering and/orcontrolling a distal region of medical device 1. Medical device 1 may beused alone or as part of a larger surgical system (not shown). Examplesof such surgical systems are described in U.S. Pat. No. 6,736,773, andU.S. Patent Publication Nos. 2011/0213206 and 2008/0188868, all of whichare incorporated herein in their entirety by reference. A distal tip 4may be operably connected to a distal region of elongate member 3 andconfigured for positioning at a work site in a body cavity. Elongatemember 3 may be flexible, or may include one or more portions that areflexible, to allow elongate member 3 to be maneuvered within the bodyand to traverse tortuous anatomical lumens. For instance, elongatemember 3 may be uniformly flexible or may include a plurality ofportions having varying degrees of flexibility or rigidity. In someembodiments, elongate member 3 may be rigid, or may include one or moreportions that are rigid.

Elongate member 3 may be formed of any suitable material, for instance,rubber, silicon, plastic, stainless steel, metal-polymer composites, andmetal alloys. In some embodiments, elongate member 3 may include layersof different materials and reinforcements. Elongate member 3 may haveany cross-sectional shape and/or configuration and may be any desireddimension that can be received in a body cavity. In some embodiments,elongate member 3 may be made of, or coated with, a polymeric orlubricious material to enable medical device 1 to more easily passthrough a body cavity.

Elongate member 3 can further include one or more channels 15, 16 (shownin FIG. 2B) extending through elongate member 3 and/or handle assembly 2and/or distal tip 4. Channels 15, 16 may have any size, cross-sectionalarea, shape, and/or configuration. Medical device 1 and channels 15, 16may be configured to deliver instruments, such as forceps, graspers,baskets, snares, probes, scissors, retrieval devices, needles, and thelike, into a patient's body. In some embodiments, channels 15, 16 couldinclude an irrigation channel for a suitable fluid, such as water orsaline, and/or an insufflation channel for insufflation gas.Accordingly, channels 15, 16 may be coupled to a fluid or gas source ata proximal region (not shown). The irrigation and/or insufflationchannels can be used, for example, to irrigate or insufflate an interiorof a body lumen. The channels may include one or more coatings to bemore lubricious.

Distal tip 4 may be located at a distal region of elongate member 3. Anexterior face 12 of distal tip 4 can define openings in communicationwith one or more channels 15, 16 in elongate member 3. These openingsmay fluidly connect channels 15, 16 in elongate member 3 to face 12 ofmedical device 1 and to regions exterior of medical device 1, as shownin FIGS. 2A-2B. For instance, an instrument passed through a workingchannel may exit a working opening 19 in distal tip 4 so that theinstrument can protrude from medical device 1 to a work site. In anotherembodiment, the instrument may be configured as an end-effector attachedat a distal region of medical device 1 and configured to pass throughworking opening 19.

The openings on face 12 of distal tip 4 may have any size,cross-sectional area, shape, and/or configuration. Further, while FIGS.2A-3B depict two channels 15, 16 exiting or terminating in distal tip 4,distal tip 4 may include an exit or termination point for only onechannel, or for more than two channels. The number, arrangement, or typeof channels included in elongate member 3 and the number, arrangement,or type of openings in distal tip 4 depicted in the embodiments areexemplary. Medical device 1 may include any suitable number, type, orarrangement of channels or openings. Further, the ratio of channels inelongate member 3 to openings in distal tip 4 need not be one-to-one.

In some embodiments, distal tip 4 may be integral with a distal regionof elongate member 3, while in other embodiments, distal tip 4 may beone or more parts separate from a distal region of elongate member 3. Insuch embodiments, distal tip 4 may be secured to a distal region ofelongate member 3 by, for example, an interference fit, a snap fit,threads, adhesive bonding, lock and key fit, or any other suitablesecuring mechanism. Distal tip 4 may be a removable or replaceabledistal tip and may be reusable or disposable. Multiple types and/orconfigurations of distal tip 4 may be available for interchangeable usewith a distal region of elongate member 3.

Further, distal tip 4 may have any useful shape to aid with procedures,deliver light, and/or diffuse light. For example, distal tip 4 may becylindrical, bulbous, hemispherical, concave, or may have angledsurfaces. In some embodiments, distal tip 4 may have rounded or bevelededges to provide increased patient comfort and to reduce the risk ofinjury to the patient.

In the embodiments in FIGS. 2A-2B and 3A-3B, face 12 of distal tip 4includes opening 19 for a working channel, two openings 20, 20′ forirrigation, suction, and/or insufflation channels, an opening 18 for anillumination unit 28, and an imaging opening 17 for an imaging unit 27.In addition, illumination opening 18 and imaging opening 17 may includewindows or lenses to cover and protect illumination unit 28 and imagingunit 27, respectively. Face 12 of distal tip 4 can include any type,number, and/or configuration of openings or units.

Units positioned in the openings of distal tip 4 may be adjacent to,flush with, or protruding from distal tip 4 and/or the channels in whichthey are oriented. Further, units may be moveable in any directionrelative to distal tip 4. For instance, illumination unit 28 or imagingunit 27 may be moveable within openings 18 or 17, respectively, in orderto aid with visualization and imaging. In other embodiments, the unitsin distal tip 4 may be stationary.

Distal tip 4 may encase various optical components. For example, suchoptical components can include image detectors, light sources,fiberoptics, light shields, filters, lenses, etc. In the embodimentshown in FIGS. 2A-2B and 3A-3B, medical device 1 may includeillumination unit 28 to illuminate a field of view at the work site andimaging unit 27 to allow a surgeon to see the work site from outside thebody and to remotely operate medical device 1 or instruments passedthrough working opening 19 to perform a desired diagnostic/therapeuticprocedure at the work site. Imaging unit 27 may be configured to captureimages and/or full-motion video images. Illumination unit 28 may beconfigured to illuminate internal body lumens and/or cavities of apatient.

Illumination unit 28 may be configured to provide both far-field andnear-field illumination. FIG. 4 depicts a cross-section of an exemplaryillumination unit 28 in illumination opening 18 located on distal tip 4.Illumination unit 28 may include one or more near-field diffusers 223,223′ and one or more far-field apertures 222. Far-field aperture 222 canbe located adjacent to, on, or be formed as a part of face 12 of distaltip 4. Far-field aperture 222 may be circular, oval, rectangular, or anyother suitable shape. Far-field aperture 222 may vary in cross-sectionalshape or size from a distal end to a proximal end. For instance,far-field aperture 222 may be conical or bowl-shaped. In one embodiment,near-field diffuser 223 may extend longitudinally away from far-fieldaperture 222 in a proximal direction. In one embodiment, a singlenear-field diffuser 223 may substantially surround the periphery offar-field aperture 222. In some embodiments, a plurality of near-fielddiffusers 223, 223′ may be located around the periphery of far-fieldaperture 222.

Distal tip 4 and near-field diffusers 223, 223′ can be monolithicallyformed (e.g., formed in one piece), or distal tip 4 and near-fielddiffusers 223, 223′ may be separate components. For instance, in someembodiments, distal tip 4 may itself be formed of a near-field diffuser223 and may surround the periphery of far-field aperture 222, or mayform the opening that forms far-field aperture 222. In one embodiment,illumination opening 18 on face 12 of distal tip 4 may define far-fieldaperture 222. When distal tip 4 acts as near-field diffuser 223, it canbe formed, for example, with a plastic or glass material. In someembodiments, distal tip 4 may be formed with a transparent material andcan be configured, for example, to filter or enhance certain wavelengthsof light. The material used to form distal tip 4 can be selected basedon the material's optical properties, such as its ability to transmitlight of a particular wavelength(s). Distal tip 4 can be, for example,molded or post-processed to form optically transmissive regions. Distaltip 4 may be made of a translucent plastic or material by any suitablemethod, including, for example, injection molding, machining, orlithography. In one embodiment, distal tip 4 may be formed of an acrylicpolymer filled with a diffuser, such as titanium dioxide. The acrylicmaterial may create a scatter effect to light that enters distal tip 4.Scattering may be facilitated by any number of ways known in the art,including fillers, opaque materials, bubbles, diffusing or opaquecoatings, surface treatments, or patterns. For example, one or moreportions of distal tip 4 may include holes, pores, particulates,bubbles, or may be partially or substantially hollowed out, or mayinclude any suitable configuration for affecting light transmission.

A light source 224 may be configured to direct light through near-fielddiffuser 223 and far-field aperture 222. Light source 224 can include,for instance, one or more optical fibers, one or more LEDs, or any othersuitable light source or combination thereof. Light source 224 can beformed of quartz, glass, plastic, or any other suitable material. In oneembodiment, a single light source, e.g., a single optical fiber or asingle LED, can be configured to direct light through both near-fielddiffuser 223 and far-field aperture 222.

Light source 224 may be positioned in line with far-field aperture 222,and one or more portions of light source 224 may be substantiallysurrounded by near-field diffuser 223. Light source 224 may be adjacentto or placed in contact with near-field diffuser 223. In one embodiment,light source 224 may extend longitudinally away from far-field aperture222 in a proximal direction. For example, light source 224 may extendfrom a proximal region through an illumination channel in elongatemember 3 to illumination unit 28 in illumination opening 18 of distaltip 4. Light source 224 may be configured to direct light through bothnear-field diffuser 223 and far-field aperture 222, and me locateddistal to one or both of near-field diffuser 223 and far-field aperture222.

Light source 224 may be recessed within distal tip 4 proximal to face12. In other embodiments, light source 224 may be flush with face 12, ormay protrude distally from face 12 of distal tip 4. Light source 224 maybe moveable relative to distal tip 4, for example, axially orrotationally.

As light from light source 224 passes through near-field diffuser 223,light rays may be spread out at a large angle such that light isdirected towards the periphery of the body lumen into which distal tip 4may be inserted. Near-field diffuser 223 may be configured to spread thelight from light source 224 that is discharged from illumination unit 28to produce a softer light that reduces harsh glare, saturation and/orhard shadows. Thus, near-field images captured by imaging unit 27 may besofter and clearer. This can result in a uniform near-field illuminationpattern.

The material and thickness of near-field diffuser 223 may affect thediffusing angle and uniformity of the illumination pattern produced byillumination unit 28. Near-field diffuser 223 can be formed of anysuitable structure, material, or combination of materials for spreadinglight from light source 224, for example, ground glass, opal glass,grayed glass, and various white opaque plastics, such as titanium-filledacrylic and glass-filled polycarbonate. In some embodiments, distal tip4 may be injection molded from any suitable, optically clear materialthat may be loaded with 1 to 15% titanium dioxide, and thus, thematerial of distal tip 4 may function as a diffuser.

Light from light source 224 entering far-field aperture 222 may not bediffused and may therefore be directed out of illumination unit 28collinear with distal tip 4. Far-field aperture 222 may be configured todirect higher-intensity, concentrated light from illumination unit 28.Accordingly, light passing through far-field aperture 222 can form acentralized, compact illumination profile, allowing for a uniformfar-field illumination pattern and improved down-lumen visualization.

The size of the aperture can determine the down-lumen spot size and thedown-lumen visualization distance. The size of far-field aperture 222can be smaller or larger than the tip of light source 224. In someembodiments, the aperture size can be variable. For instance, far-fieldaperture 222 may be operably coupled to proximal handle assembly 2 andconfigured so that a user may adjust the size of far-field aperture 222.In one embodiment, one or more illumination units 28 may be operablyconnected to one or more imaging units 27. In this embodiment, forinstance, the size of aperture 222 may be automatically adjusted basedon signals received and/or processed from imaging unit 27. In otherembodiments, the size of far-field aperture 222 may be fixed. Far-fieldaperture 222 may also include a cover, filter, diffuser, or any othersuitable structure to control far-field illumination.

The properties of far-field aperture 222 and near-field diffuser 223 canbe tailored depending on the requirements of the type of medical device1 used or the therapeutic or diagnostic procedure performed.Furthermore, distal tip 4 may include multiple light sources 224—eithera bundle of optical fibers or an array of LEDs in a single illuminationunit 28, or multiple illumination units 28 using single or multipleoptical fibers or LEDs—to increase light intensity and/or to alter theillumination pattern.

In some embodiments, distal tip 4 may house components that are uniqueto distal tip 4 and do not extend through channels in elongate member 3,or that only partially extend through channels. For instance,illumination opening 18 in distal tip 4 may or may not fluidly connectwith one or more corresponding channels extending through elongatemember 3 and instead may terminate within a recess in distal tip 4. Forexample, while working opening 19 in distal tip 4 may fluidly connectwith a working channel in elongate member 3, optical components may ormay not extend through corresponding channels in elongate member 3, ormay only partially extend through a channel. Imaging unit 27 and/orillumination unit 28 may or may not be entirely contained in openings 17and 18, respectively, in distal tip 4.

In one embodiment, an optical component can extend within an opening ofdistal tip 4 such that a distal end portion of the optical component isencased within distal tip 4 and a proximal end portion of the componentcan extend out a proximal end of distal tip 4 and through a channel ofelongate member 3. For example, optical components having a power lineor signal line, such as light source 224 (FIG. 4) in illumination unit28 or a component in imaging unit 27, can have a power line or signalline extending out of a proximal end of distal tip 4. Imaging unit 27can be coupled to a proximal imaging controller (not shown) viaconductors, such as electrical wires, passing through a channel ofmedical device 1, as described above. Thus, images of a body lumen canbe captured by imaging unit 27 and processed by the imaging controller.The images can also be communicated to an eyepiece or display device(not shown). Imaging unit 27 may include a camera, lens, digital-imagingchip, or other image-receiving device, which may transmit signals usingwire or cable within a channel of elongate member 3.

As alluded to above, medical device 1 may be coupled to a control moduleand may include imaging electronics configured to process and/ortransfer signals received from imaging unit 27 to a display (not shown)for viewing by a user. The control module may also be operably connectedto light source 224, such as a fiber optic source, halogen source, orLED source, configured to deliver light to illumination unit 28, and/orillumination electronics configured to process and/or transfer signalscontrolling illumination unit 28. One or more actuators or buttons maybe disposed on the control module to control illumination unit 28 and/orimaging unit 27. Alternatively, the one or more actuators or buttons maybe disposed on handle assembly 2 of medical device 1 for controllingillumination unit 28 or imaging unit 27.

In one embodiment, illumination unit 28 may be operably connected tohandle assembly 2 and may provide a communication pathway between acontrol module and both imaging unit 27 and illumination unit 28. Forexample, a connector may provide electronic signaling pathways forimaging unit 27 to transmit image data to a control module, for acontrol module to transmit image control signals to imaging unit 27, andfor a control module to control light delivered from light source 224 toillumination unit 28. It should be appreciated that in otherembodiments, however, light source 224 may be housed in handle assembly2, and illumination unit 28 may be operably connected to light source224 within handle assembly 2. Light source 224 may then be operablycoupled to a control module via a connector.

A connector may include any appropriate linkage configured to providesignaling capabilities and communication between a control module andboth imaging unit 27 and illumination unit 28, such as, for example, oneor more electrical wires, an electrical conduit, or other suitableconnectors. A connector may also include a suitable structure configuredto readily attach and detach from a control module, such as, forexample, a detachable point-to-point adapter, a detachable splice, and adetachable multi-port adapter. The one or more electrical wires mayextend from handle assembly 2, through a channel in elongate member 3,and connect to imaging unit 27 in imaging opening 17 at distal tip 4.Illumination unit 28 may also extend from handle assembly 2, through achannel in elongate member 3, and terminate in illumination opening 18at distal tip 4.

A user may control light directed through light source 224 andillumination unit 28 jointly or independently of a control system tooptimize visualization. One or more than one light source 224 and one ormore than one imaging unit 28 may be centerplated on distal tip 4 andcontrolled by a user. Further, a user may independently control thecharacteristics of light using, for instance, controls located on handleassembly 2, or a control system (not shown) may control thecharacteristics of light. The characteristics may include intensity,wavelength, polarization, color, frequency, phase, or any othercharacteristic that can vary the level of illumination directed throughlight source 224 and/or illumination unit 28. For instance, lightdelivered from light source 224 and/or illumination unit 28 may becolored or white, filtered or unfiltered, pulsing or steady, intense ordull, e.g., and these characteristics may be constant or may change, forinstance, automatically, in response to user control, or according topreset conditions.

Any aspect set forth in any embodiment may be used with any otherembodiment set forth herein. Every device and apparatus set forth hereinmay be used in any suitable medical procedure, may be advanced throughany suitable body lumen and body cavity, and may be used for treatmentor observation of any suitable body portion. For example, theapparatuses and methods described herein may be used in any natural bodylumen or tract, including those accessed orally, vaginally, or rectally.

The many features and advantages of the present disclosure are apparentfrom the detailed specification, and thus, it is intended by theappended claims to cover all such features and advantages of the presentdisclosure that fall within the true spirit and scope of the presentdisclosure. Further, since numerous modifications and variations willreadily occur to those skilled in the art, it is not desired to limitthe present disclosure to the exact construction and operationillustrated and described, and accordingly, all suitable modificationsand equivalents may be resorted to, falling within the scope of thepresent disclosure.

What is claimed is:
 1. A medical device, comprising: an elongate memberincluding a proximal region and a distal region; a handle at theproximal region of the elongate member, and a tip at the distal regionof the elongate member, wherein the tip includes one or more openings,wherein one of the one or more openings at least partially houses anillumination unit, comprising: a light source; a near-field diffuserproximate to the light source; and a far-field aperture proximate to thelight source.
 2. The medical device of claim 1, wherein the illuminationunit is configured to provide near-field illumination and far-fieldillumination.
 3. The medical device of claim 1, wherein the near-fielddiffuser is adjacent to the light source and substantially surrounds aportion of the light source, and the far-field aperture is distal to thelight source.
 4. The medical device of claim 1, wherein the tip ismonolithic with the near-field diffuser.
 5. The medical device of claim4, wherein the tip or the near-field diffuser defines the far-fieldaperture.
 6. The medical device of claim 1, wherein the elongate memberincludes one or more channels extending from the proximal region to thedistal region.
 7. The medical device of claim 6, wherein the lightsource is operably connected to the handle by a connector extendingthrough one of the one or more channels in the elongate member.
 8. Themedical device of claim 1, wherein the distal face of the light sourceis recessed within the tip proximal to a distal face of the tip.
 9. Themedical device of claim 1, wherein the tip further comprises at leastone opening containing an imaging unit.
 10. The medical device of claim9, wherein the imaging unit is operably connected to the illuminationunit.
 11. The medical device of claim 9, wherein the imaging unit andthe illumination unit are operably connected to a controller external tothe medical device.
 12. The medical device of claim 1, wherein thenear-field diffuser is glass or plastic.
 13. The medical device of claim1, wherein the light source includes only one optical fiber.
 14. Themedical device of claim 1, wherein the light source includes only onelight emitting diode.
 15. A medical device, comprising: an elongatemember including a proximal region and a distal region, and includingone or more channels extending from the proximal region to the distalregion, wherein a channel of the one or more channels is configured tocarry light or a light signal to a distal region of the elongate member;and wherein the light or light signal is from only one optical fiber oronly one light emitting diode; a near-field diffuser at the distalregion of the elongate member and configured to provide near-fieldillumination; a far-field aperture at the distal region of the elongatemember, wherein the far-field aperture is configured to providefar-field illumination; and an imaging unit.
 16. The medical device ofclaim 15, wherein the near-field diffuser is monolithic with the distalregion and the far-field aperture is defined by the distal region. 17.The medical device of claim 15, wherein the channel includes the onlyone optical fiber, the near-field diffuser surrounds at least a portionof the optical fiber and the far-field aperture is narrower than a widthof the optical fiber.
 18. The medical device of claim 15, wherein thefar-field aperture is located distal to the optical fiber or the lightemitting diode.
 19. The medical device of claim 15, wherein thefar-field aperture is located distal to a distal face of the near-fielddiffuser.
 20. The medical device of claim 15, further comprising ahandle assembly at the proximal region of the elongate member, whereinthe handle assembly houses at least part of the optical fiber or atleast part of the light emitting diode.